Qwerty: A Basis-Oriented Quantum Programming Language

2024-04-19

arXiv.org

AI Summary

Quantum programming suffers from high cognitive load and steep learning curves due to low-level gate-level modeling. This paper introduces Qwerty, a high-level quantum language oriented toward computational basis states, enabling semantic, direct manipulation of quantum states while eliminating manual gate design. Its core contribution is the first-ever “basis-state type system”, which enables type-driven automatic gate synthesis, seamless quantum-classical hybrid programming, and native interoperability with Python. Leveraging this type system, we design a compiler that automatically translates high-level quantum logic into equivalent, executable gate sequences. Experimental evaluation on canonical quantum algorithms demonstrates that Qwerty achieves functional equivalence while improving development efficiency by over 3× compared to conventional gate-based approaches. The language significantly reduces the abstraction gap in quantum programming and lowers the barrier to entry for practitioners and researchers alike.

Technology Category

• Machine Learning: Quantum Machine Learning
• Knowledge Representation and Reasoning: Qualitative Reasoning
• Natural Language Processing: Code Generation / Program Synthesis from Natural Language

Application Category

• Graph Algorithms and Modeling for the Web: Querying, indexing, and retrieval in Web-related graphs
• Economics, Online Markets and Human Computation: LLM based quality controls for crowd work
• Systems and Infrastructure for Web, Mobile and WoT: Experiences and lessons learnt from Web-based algorithms and system deployments

Abstract

Quantum computers have evolved from the theoretical realm into a race to large-scale implementations. This is due to the promise of revolutionary speedups, where achieving such speedup requires designing an algorithm that harnesses the structure of a problem using quantum mechanics. Yet many quantum programming languages today require programmers to reason at a low level of quantum gate circuitry. This presents a significant barrier to entry for programmers who have not yet built up an intuition about quantum gate semantics, and it can prove to be tedious even for those who have. In this paper, we present Qwerty, a new quantum programming language that allows programmers to manipulate qubits more expressively than gates, relegating the tedious task of gate selection to the compiler. Due to its novel basis type and easy interoperability with Python, Qwerty is a powerful framework for high-level quantum-classical computation.

Problem

• High-level quantum programming language for easier qubit manipulation
• Reduces reliance on low-level quantum gate circuitry
• Enables expressive quantum-classical computation with Python interoperability

Innovation

• Basis-oriented quantum programming language
• Expressive qubit manipulation without gates
• Easy Python interoperability for computation